| 摘要 |
<p>1472635 Automatic control INTERCONTINENTAL TRADING CO 4 July 1974 [12 July 1973] 29654/74 Heading G3N A control apparatus for a machine, operating on a workpiece by a relatively displaced tool, imposes a programme of speeds on the displacement in response to sensing photo-electrically a programming element, having zones of varying transparency or reflectance, a complete translation of which corresponds to one complete movement along the path. As shown, a machine for grinding the edges of a glass plate 84 comprises conveyer belts 70, 72 driven through pulleys 74, 76 and a reduction gear 82, by a motor 80. A switch 128 is actuated by the passage of the plate to energize a clutch 106 coupling a programme device to the conveyer drive. The programme device comprises bands 114, 116, having zones of varied transmittance or reflectance, the length of the band and a drivecoupled pulley being such that the band makes one circuit during the passage of plate 84. The zones are sensed by an optical scanner 126 and the signals derived from band 114 controls the speed of the motor 80 while signals from band 116 control jacks 102, 104 pivoting arms 98 about a shaft 100 whereby grinding wheels 92, 94, driven by motors 96, are applied to the edges of the glass plate. In an alternative embodiment a disc having areas of varying transmittance or reflectance, is sensed to control a steel or tungsten cutting wheel. The areas on the disc or bands are scanned by photo-cells which control switches connecting binary-valved resistors providing a reference signal to an amplifier controlling a drive motor. Rate feedback is provided by a tachometer.</p> |
